How to defeat belief in the external world

I defend the view that there is a privileged class of propositions -that there is an external world, among other such 'hinge propositions' -that possess a special epistemic status: justified belief in these propositions is not defeated unless one has sufficient reason to believe their negation. Two arguments are given for this conclusion. Finally, three proposals are offered as morals of the preceding story: first, our justification for hinge propositions must be understood as defeatable, second, antiskeptics must explain our knowledge in the face of 'actual world' skepticism (like dreaming skepticism) as much as in the face of the usual sort (like brain-in-vat skepticism), and, finally, our justification for hinge propositions is basic (i.e. non-inferential).